kbuild: deb-pkg: make debian/rules quiet for 'make deb-pkg'

Add $(Q) to the commands in debian/rules to make them quiet when the
package built is initiated by 'make deb-pkg' or when the 'terse' tag
is set to DEB_BUILD_OPTIONS.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>